106 THE WONDERFUL CENTURY. CHAP. xi. 



vast host of phenomena which, till quite recently, were 

 isolated or misunderstood. 



Beginning with the meteoric masses which at con- 

 siderable intervals fall upon the earth, and the meteoric 

 or cosmic dust which in minute spherules is probably 

 always falling since it is found abundantly in all the 

 deepest oceanic deposits far removed from continental 

 land we have next the meteor streams with their at- 

 tendant comets, circling round the sun in vast numbers, 

 and increasing to such an extent in his vicinity that they 

 become visible as the zodiacal light ; the planetoids, ever 

 increasing in recorded numbers and probably forming 

 the larger members of a vast meteor ring; and the rings 

 of Saturn, now proved to be of the same meteoritic 

 nature. Then, passing on to the interstellar spaces, we 

 find the nebulae, which are but vast uncondensed meteor 

 swarms; the planetary nebulae and nebulous stars being 

 examples of greater condensation, leading on to the 

 myriads of the starry hosts, each one a sun heated by 

 the inward rush and titanic collisions of countless 

 meteor-swarms. These suns, after reaching a maximum 

 of heat and light, slowly cool into darkness, until a col- 

 lision with other cosmic matter again heats the mass to 

 incandescence or even to vaporization all this grand 

 series of phenomena, rising from dust particles on the 

 ocean bed to a million million of suns, comprehended, 

 and to some extent explained, by one of the simplest and 

 at first sight most inadequate of hypotheses that of a 

 meteoritic origin of the material universe. 



It has been objected that this theory is not so simple 

 as the old nebular hypothesis, and has no advantages 

 over it. But this is a mistake. The latter begins with 



